This invention relates generally to compositions containing an organic liquid and a sorbitol acetal gelling agent, which are useful in cosmetic sticks, such as antiperspirant and deodorant sticks. In particular, the invention relates to a stable dispersion of dibenzylidene sorbitol acetal (DBS) and a diol.
The use of DBS to gel organic liquids is well known. For example, DBS has been disclosed as a gelling or thickening agent for polyester (U.S. Pat. No. 3,767,729), hazardous liquids such as light oil (JP-B-77-043555), coal pitch or oil pitch (JP-B-77-028821), water and alcohol mixtures (JP-B-86-8695), and oil spills (U.S. Pat. No. 4,502,975).
The use of DBS to gel cosmetic stick compositions is also well known and exemplified in CA-A-2,064,179. Briefly, an astringent salt and/or an antibacterial agent are dissolved in a solvent, such as propylene glycol, along with DBS. Upon cooling, the DBS forms a network or matrix in the composition, causing the composition to gel.
In the manufacture of cosmetic sticks, it may be desirable to add the DBS to the composition in the form of a concentrated dispersion in an organic solvent. Since the dispersion must be pumped or poured, it is critical that it not gel or otherwise plug equipment and transfer lines. Consequently, there is an attendant risk in preparing concentrated dispersions of DBS in an organic solvent, that even under ambient conditions, the composition may gel, resulting in lost production.
Dibenzylidene sorbitols having various substituent groups on the aromatic rings, such as 1 to 3 alkyl or halo groups, are well known in the prior art and many are commercially available. The substituted DBS gelling agents and dibenzylidene sorbitol itself are referred to generally herein as "DBS compounds". DBS for use in gelling organic liquids is available under the trademark MILLITHIX 925.RTM. from the Milliken Chemical Division of Milliken & Company, Spartanburg, South Carolina. The product is sold with a specification of 1 to 2 wt. % water.